Self-centering rollers



July 1968 E. w. DOHANYOS 3,39

SELF-CENTERING ROLLERS Filed March 9, 1966 INVENTOR sew G 3 EDWARD w. DOHANYOS ATTORNEY United States Patent 3,393,784 SELF-CENTERIN G ROLLERS Edward W. Dohanyos, 1134 Stillson Road, Fairfield, Conn. 06430 Filed Mar. 9, 1966, Ser. No. 533,007 1 Claim. (Cl. 19335) ABSTRACT OF THE DISCLOSURE A load centering and conveying device for moving a load wherein said load has at least two skids connected thereto. Said device having a frame with two rows of rollers thereon with each roller being pivotally mounted about a vertical axis. Spring means are used to maintain each roller in a predetermined position without a load being placed thereon and a stop means is provided for limiting the rotation of each roller about its vertical axis. The lateral distance between each row of rollers being approximately equal to the center-to-center distance between the cooperating skids so that the skids will seek the centers of their respective rollers when they go off center.

This invention relates to roller conveyors and more particularly to conveyors for transporting objects whose weight rests on the roller.

It is an object of this invention to provide a roller which is pivoted about a vertical axis passing through the center of the roller so that a load will seek the center of the roller when the load goes off the center of the roller due to roller action.

Another object of this invention is to provide stops to limit the pivotal movement of the roller.

It is a further object of this invention to provide a double row of pivotally mounted rollers to convey a pallet having skids located the same distance apart as the pivotal mountings of the rollers.

Another object of this invention is to provide spring means to maintain a roller to a predetermined neutral position.

Other objects and advantages will become apparent from the following specification and the attached drawings.

FIG. 1 is a perspective view of a boat trailer having the rear roller installed using this invention.

FIG. 2 is a perspective view showing two lines of rollers using this invention with a pallet and load positioned thereon.

FIG. 3 is an end view of a roller using this invention, and

FIG. 4 is a top view of a roller using this invention.

Referring to the drawings, FIG. 1 shows a trailer having laterally spaced wheels 4 fixed on the ends of an axle 6 which is suspended below a frame 8 by springs 10. The frame 8 has two side members 12 with front and rear transverse members 14 and 16 respectively. A front roller assembly 18 is fixed at the center of the front member 14 and a rear roller assembly 20 is fixed at the center of the rear member 16.

The rear roller assembly 20 is shown enlarged in FIG. 3. A bracket is bolted to the member 16 having an enlarged boss 32 with a vertically aligned opening 34. A bearing member 36 is fixed within said opening. A roller 40 is rotatably supported in a U-member 42. The U- member 42 has a supporting shaft 44 extending down therefrom which engages the bearing member 36. The top of the supporting shaft 44 is enlarged at its top and forms an annular step at 46 where it is necked down to engage the inner surface of the bearing member 36. This step 46 rests on the top of the bearing member 36. A locked washer 48 is placed over the bottom part of 36 as it projects downwardly from the boss 32. A spring 50 "Ice extends around the top of the supporting shaft 44 and is' fixed at one end to the U-member 42 and its other end to the boss 32. A second spring '52 is positioned around the lower portion of the reduced portion as it extends below the boss 32. The spring has one end attached to the reduced portion of shaft member 44 at its other end to the boss 32. Each of these springs has its biasing force in opposite directions so that they tend to maintain the roller in a given position. Two stops 60 and 62 are provided to limit the degree of movement of the roller.

FIG. 2 shows two lines of rollers 40 mounted in the same fashion as in FIG. 3. The pallet 70 has two skids 72 and 74 which are mounted apart the same distance as the shaft members 44A and 44B of the rollers under them.

- Operation It can be seen that a load travelling across the roller 40 tends to reposition itself over the vertical pivot axis of the roller, provided by supporting shaft 44, as it starts to go away from such vertical pivot axis. This is due to the fact that as the skid 74 goes to one side of the center of the vertical pivot axis, the roller 40 will pivot forward on that side causing the roller to be diagonal to the skid and this, combined with the normal roller action, will cause the skid to return to the center of the vertical pivot axis again placing the roller perpendicular relative to the skid.

It will thus be seen that by providing a double pivoting action, that is, the roller pivoting about its horizontal axis as well as its vertical axis, the present invention provides a solution to the problem of keeping a load on the center of a roller as the load is being transferred across said roller.

This ability to have the load that is travelling across the roller seek the center of the roller, considerably facilitates the loading and reloading, by a single person, of a boat on a trailer equipped with this invention.

It is to be understood that the invention is not limited to the specific description above or other specific figures, but may be used in other ways without departure from its spirit as defined by the following claim.

I claim:

1. A load centering and conveying device for load carrying means having at least two skids which comprises:

(a) a frame;

(b) at least two rows of roller supports aligned parallel to the longitudinal axis of the frame and each mounted on the frame for rotation about a vertical axis;

(c) a roller mounted within each roller supported for rotation about a horizontal axis for contacting a skid;

(d) spring means for each roller support to urge the roller to a position placing the horizontal axis of rotation of the roller approximately perpendicular to the longitudinal axis of the frame;

(e) stop means on the frame for limiting the rotation of each roller support about its vertical axis; and

(f) the lateral distance between each row of roller supports being approximately equal to the center-tocenter distance of the skids so that the skids of the load carrying means seek the centers of their respective rollers when they go off center.

References Cited UNITED STATES PATENTS 758,989 5/1904 Lucas 19342 1,541,300 6/1925 White et al. 19342 1,760,304 5/1930 Feldin 19342 3,056,517 10/1962 Trumbull 21484 ALBERT J. MAKAY, Primary Examiner. 

